"2D Dogfight - Secret Project" DLC includes the following 12 Aircrafts:

Mitsubishi F-1
F-14D Super Tomcat
F-15EX Eagle II
F-5E Tiger 2000
Kurnass 2000
IAI Lavi
MiG-31BM Foxhound
Su-47 Berkut
Tejas Mk.1
X-29
X-31
Ye-8
F-101A Voodoo
Shenyang J-8H
MiG-29SMT
Mirage 4000

Players who purchase this DLC can use these aircrafts in custom game, online game and some Campaigns.

In addition, players who purchase the DLC can also get the exclusive menu wallpaper and red theme UI of "Secret Project"